The problem is that people do not want to invest the time to customise. They want it it look good from the start. They want it to make sense from the start.

Opera and Firefox (and other browsers) look pretty much the same from the start: http://i27.tinypic.com/en77n.png Or am I missing something? If the problem is the Opera logo in the title bar, then I tend to think the problem of Opera is not a technical problem, but rather a brand problem. People dislike Opera because it's Opera.

people now want extensions

Not people, geeks.

which are not available for Opera.

No need, these functionalities come already out of the box. Isn't it better? Who wants to chase for extensions that not always work across upgrades?

It should blend in on Vista, XP, KDE, OSX.

Now, this is interesting. Opera has native OS integration in Vista, XP, KDE and OS X. However, Firefox doesn't have native integration for KDE, although it has for Gnome because Opera uses Qt and Firefox uses Gtk.

They are innovators, but they are not presenters.

I really don't think the problem is a GUI issue. It's rather a branding issue. Who here dislikes the Opera application but likes the Opera Software company itself? I'm sure not many.

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Now, this is interesting. Opera has native OS integration in Vista, XP, KDE and OS X. However, Firefox doesn't have native integration for KDE, although it has for Gnome because Opera uses Qt and Firefox uses Gtk.
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I really don't think the problem is a GUI issue. It's rather a branding issue. Who here dislikes the Opera application but likes the Opera Software company itself? I'm sure not many.

Opera always feels odd. It may not be any different but it always makes me work harder to do things. e.g., I thought it was great that they had PhishTank integration. I thought that it was ridiculous that I had to activate it. For similar reasons, I don't use Safari unless I need something specific.

Opera is a third browser on all my systems, even when I only have two browsers installed.